From: "H. Peter Anvin" <hpa@zytor.com>
To: Thavatchai Makphaibulcboke <thavatchai.makpahibulchoke@hp.com>
Cc: Lasse Collin <lasse.collin@tukaani.org>,
"lethal@linux-sh.org" <lethal@linux-sh.org>,
"tglx@linutronix.de" <tglx@linutronix.de>,
"mingo@redhat.com" <mingo@redhat.com>,
"x86@kernel.org" <x86@kernel.org>,
"kaloz@openwrt.org" <kaloz@openwrt.org>,
"matt.fleming@intel.com" <matt.fleming@intel.com>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"linux-s390@vger.kernel.org" <linux-s390@vger.kernel.org>,
"linux-sh@vger.kernel.org" <linux-sh@vger.kernel.org>,
"linux@arm.linux.org.uk" <linux@arm.linux.org.uk>,
"schwidefsky@de.ibm.com" <schwidefsky@de.ibm.com>,
"heiko.carstens@de.ibm.com" <heiko.carstens@de.ibm.com>,
"linux390@de.ibm.com" <linux390@de.ibm.com>
Subject: Re: [PATCH] lib/decompress_unxz.c: removing all memory helper functions
Date: Fri, 25 May 2012 10:13:50 -0700 [thread overview]
Message-ID: <4FBFBDCE.6030104@zytor.com> (raw)
In-Reply-To: <4FBFBBF3.3090204@hp.com>
On 05/25/2012 10:05 AM, Thavatchai Makphaibulcboke wrote:
>> We could do that. But according to the comment in the original
>> implementation, there seems to be a concern regarding its performance
>> speed. If you believe all archs' memcpy would give comparable
>> performance to the memmove. then I could do that.
>>
>
> Also how about the case for overlapping buffer, especially when the
> destination is at a higher address? I do not believe memcpy guarantee
> to work.
memcpy() is not guaranteed to work for any overlap; that is what
memmove() is for.
-hpa
--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.
next prev parent reply other threads:[~2012-05-25 17:15 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-24 16:03 [PATCH] lib/decompress_unxz.c: removing all memory helper functions T Makphaibulchoke
2012-05-24 17:26 ` Joe Perches
2012-05-24 17:29 ` H. Peter Anvin
2012-05-24 17:40 ` Joe Perches
2012-05-24 17:41 ` H. Peter Anvin
2012-05-24 17:50 ` Joe Perches
2012-05-24 17:56 ` H. Peter Anvin
2012-05-25 8:34 ` Lasse Collin
2012-05-25 16:31 ` Thavatchai Makphaibulcboke
2012-05-25 17:05 ` Thavatchai Makphaibulcboke
2012-05-25 17:13 ` H. Peter Anvin [this message]
2012-05-25 19:35 ` Lasse Collin
2012-05-28 7:03 ` Jean-Christophe PLAGNIOL-VILLARD
2012-06-01 2:48 ` Thavatchai Makphaibulcboke
2012-06-01 2:54 ` Joe Perches
2012-06-01 3:38 ` H. Peter Anvin
2012-06-01 18:37 ` Thavatchai Makphaibulcboke
2012-06-01 18:46 ` H. Peter Anvin
2012-06-01 18:58 ` Thavatchai Makphaibulcboke
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